Due to having high electron mobility, application of a MOSFET (Metal Oxide Semiconductor Field Effect Transistor) with a compound semiconductor is desired. For example, Non-Patent Document 1 discloses oxidation processing of InAlAs and applications of this processing for semiconductor wafers used in manufacturing semiconductor devices. Specifically, Non-Patent Document 1 describes, based on an assumption of use as a gate insulating layer in an HEMT (High Electron Mobility Transistor) that is an InAlAs/InGaAs-based MOS, forming a semiconductor wafer by oxidizing an n-type InAlAs layer above an InGaAs layer functioning as a channel layer.
Non-Patent Document 1: N. C. Paul et al., Jpn. J. Appl, Phys., Vol. 44 (2005), No. 3, pp. 1174-1180